Power train and control mechanism



Sept. 27, '1960 M. J. MACK.EIT AL 2,953,935

POWER TRAIN AND- CONTROL MECHANISM I Filed Dec. 1, 1958 a ll FIG. 2

Sept. 27, 1960 M. J. MACK ET AL 2,953,935

} POWER TRAIN AND CONTROL MECHANISM Filed Dec. 1, 1958 2 Sheets-Sheet 2 r as INVENTORS 7 I 2 M.J.MACK 92 E.H.FLETCHER a 8 82 LRHARVEY United States Patent -to Deere -& Company, Moline, Ill.,.a corporation of Delaware Fileil Dec. 1, T 1958, Ser.- No. 777,413 'l-Claims. (Ch n-41 3) This invention relates to a ;power train -:and control mechanism therefor and more particularly to a power train having a pair of disconnectible'means operative in series and control means for causing these-means to ."mmctiondnrthezdesiredrsequence.

flhe'sinvention 'finds particular"utility -in the controlaof aalpowerrtakewlf, ;as-iin*an agricultural tractor, wherein ittheienginetaorztransmission contains avdrivexshaft which idseconnectedzbyzacfnictionxclutch r-toaan intermediate shaft nilhich is pint-turn zconnectedtto :the :power .take-oif shaft i'by aipositivesclutch. lWhenit is desired:toidleathegpower eitalcemfftshaftgthe'positive clutch .is'idisengaged. iWhen Th-BEPGWEIMEZICC OE a'shzift isiin use but must be Fintermitztentl-y Tstopped, the :positive nclutch fis iengage'd wand ithe rfrictionwclutchzis msed :for the intermittent engagement adisengagement. "Heretofore, fthe 'roperation of the :two rclutches has :heen zachieved by two :control :levers. AceorIling to thegpresentvinvention, ia-isingle controlimeans is :pmvided sand is :arrangedso that :the :sequential :operation of' it-he ztwo celutches :occurs in the :idesired torder; :disconnected, 'theroontro'l means rfun'ctions toifirstfdisengage the triclion clutch, ithen to engage lthe; positiveaclutch anrl :then to ree'ngage the friction clutch, and is :thereafter eaper- "ative'lto engage-and: disengage 'the f fI'lCilOIlTllliCh Without :aifecting the positive clutch. In instances in which iit ris desired-a0 disconnect the power :take=off "shaftzior is; prolen-ge'd period, the control means operates :toztfirst adisenga'ge fth'e fri'cti'on clutch, then to disengage the cpositive e1uteh and then to reengage the :friction i clutch While -leaving the positive.clutch disengaged.

lt is "a further object at the invention to provide an improved and novel-control -'means" having.relatively few =parts,-one"that is fool=proofin operation, and one -that i's' easily used and readily serviced. Further-objects re- "side in improvements of the power 'tr'ain in which the two clutches are operative' inseries.

"The foregoing -and other "important objects and desirable features inherent in and encompassed by-the invention will become apparent'as a preferred embodiment "thereof is disclosed, by *way'of example, in the ensuing description and accompanying sheets of drawings, the scverah'figuresof which are descr'ibed'be'low.

Fig. l is a fragmentary perspective, with portions broken away, illustrating the overall control arrangement "and power train.

"j-Fig. "2 is an enlarged section as seen generally along the line22ofFig. 'l a Fig. 3 is an enlarged elevation of the control mechafin's'm, illustrating 'oneposition thereof in full lines and anotherpositi'on in broken lines. 7 V

"Fig. 4 is a similar "view but illustrates a third posi- "tionof the'control means.

7 Fig. is 'a section as seen generally along "the line 5-. 5 o'f'Figx4. r

As indicatedthe "invention finds its greatest "utilityin the control of power take-off shafts in agricultural tracposition.

shown at 5-2. When the shaft Patented Sept. 27, "1960 tors and the present environment w'ill"be bas'e'd thereon. "Thetnumeralltl represents a tractor transmission case i or housing 'havinga side wall 1'2in'which1is appropriatel y mounted a support 14 having .a'tubular 'p'ortion'or sleeve 16 in which is rockably carried 'atubu1a'r'shafti18. A solid shaft 20 islconcentrically journaled 'within'the tubular shaft 18.

Within the transmission lease and mountedin any suitable manner are .a driveshaft22, a coaxial intermediate shaft 7.4 and a coaxial output-or power takemfi shaftl2'6. A typical friction clutch28 .is selectively connectible and disconnectible between the shafts'22 and 24 andia clutch of thepositive type, as a630, is selectively eonne'ctible and 'disconnectible between'the shafts '24 and "'26. .As shown in 'Fig. '1, the clutch 30 is disconnected. IThe clutch'28 is spring loaded tosan engaged or connected An operating arm 32 is keyed to the inner end .of the solid shaft 20 and-is connected in turnby a link '34 to a throw-out rod or shaft 36 whichlin 'turn' has va 'fork 38'connected to the clutch '30. A conventional 'detent :40 holds the two positionsof the rod'36, which correspond to engaged and disengaged positions of the clutch 30. Stated .otherwise, when the shaft '20 and arm 32 .arerocked clockwise fromthe position shown in Fig.

.1, .the clutch 30 will move forwardly or to the left as seen by the reader, engaging the clutch 30 between the shafts 126 and '24, the proximate ends of which are appropriately splined as indicated.

lliheinner-end of the tubular shaft 18 rigidlytcarries an .arm 42 which issuitably connected by a link 44 to a throw-outlever 46,pivoted at 48 on-any suitable part of thecasing. .The lever 46 operates conventionally. in conjunction withsa throw-out .collar 50 which in turn .operates typical clutch throw-out'levers, one of which is 18 and arm -42-are rocked in a clockwisewdirection as seen in Fig. 1, thelever 46 is rocked forwardly about its pivot 58 to cause the throw- "out collar 50 to depress the clutchlever 52::for disengagvingthe clutch. 28. Thespring loadingin the c'lutch '(not shown.) restores the clutch to engaged position.

The .mechanism for-controlling the power trainfjust describedlis external 'to'the casing 10, whereas the-pow- -er trainis within the casing, with the exception of "the power take-off shaft '26 project .rearwardly atthe back of the tractor for conwhich,.in a typical .situation,-w'ill nection .to associated implements used with the tractor. The significance of the arrangement o f'the twoclutches .28 and .30 in series is,..as-already briefly described, that when:it isdesired to use the power take-off .shaftl2 '6, the

clutch 30 will be connected andthe clutch '28 'willlbe selectively-engaged and disengaged to control-the intermittent operation of the .power take-off shaft. When the power take-off shaft is :desired to be d-isconnected for prolonged periods, the clutch 30 can be disconnected. This avoids thenecessity of using an overcenter. arrangementon theclutch 28 to disconnect the'power-take-oif shaft, as hasbeen used on prior: occasions.

The -.control mechanism is mounted attheouter .or V

left hand end of the support :sleeve '-1-6-which,- as,,previously described, :serves to journal the twoconcentric shafts 1'8 and20. The outer end of the shaft 20 carries a rearwardly'extending arm 54, andthe connection .is

-rigid, -as by 'a pin 56. A second arm or member z58iis keyed at 60 to-the outer end-of the tubular shaft :18. The member or arm 58 may be made up oftwo-epieces,

one-of which at 62 carries the key =60'and the otherof which at 64 is adjustably connected to the part 62 ':by slots 66 :ands-cap screws 68. This arrangement enables angular. adjustment of the parts 62 and 64relative .to each "other about the common axis of-the shaft-S118 and 20. The 'two arms "54 and '58 are interconnected by linkage including a first link 70 comprising a pair of straps pivoted at 72 at their lower ends to the free or rear end of the arm 54- and rising therefrom to a terminal end carrying a pivot 74. Another part of the linkage is a second link or lever 76 pivotally connected to the link 70 at 74 and fulcrumed at 78 on the upper or free end of the arm or member 58. A forward extension of the link or lever 76 serves as a handle 80 for convenience of the operator. The pivots at 72, 74 and 78 are on axes parallel to the common axis of the shafts 18 and 20.

The handle 80 constitutes a single means for controlling both clutches, which is accomplished by means of a guide 82 having a forward portion 84 rigidly secured to the support sleeve 16 and a rearward plate-like portion 86 in which are formed first, second and third slots 88, 90 and 92, respectively. A guide or track follower 94 controls the linkage 70-76 via the tracks or guides afforded by the three slots just described so that the clutches 28 and 3t operate in sequence in a manner to be outlined below.

Figs. 1 and 3 show (the latter in full lines) the position of the control mechanism when the clutch 28 is engaged and the clutch 30 is disengaged. In this status, the arm 54 occupies a position in which its pivot 72 is in what may be termed a first position, hereinafter referred to as position A. The follower 94 is in the forward part of the upper arcuate slot 88, which is arcuate about the point A as a center. Consequently, the operator, by means of the handle 80, may rock the member or arm 58 about the common axis of the shafts 18 and 2t rocking the shaft 18, since the member 58 is keyed to the shaft 20 at 6%). This will disengage the clutch 28 via the arm 42, link 44, lever 46, throw-out collar 50 and clutch lever 52. Since the slot 88 is arcuate about point A, the link 70 will merely swing about point A and will have no effect on the clutch 30. Therefore, the clutch 23 may be engaged and disengaged without changing the position of the clutch 30.

When the member 58 is moved to its full rear position so that the follower 94 is at the rear end of the slot 83, or at the upper intersection of the slot 88 with the cross-over slot 90, as shown in broken lines in Fig. 3, the handle 80 may be pulled upwardly to rock the link 76 about its fulcrum 78 on the rearwardly positioned member 58, which transmits a force in compression to the link 70 which in turn is converted to rocking movement of the solid shaft 20 as the link 70 pushes down on the arm 54, thereby swinging the arm 32 forwardly and pulling forwardly on the link 34 and rod 36 so that the clutch 30 is shifted forwardly to connect the shafts 24 and 26. This connection of the clutch 38 occurs while the clutch 28 is retained in disengaged position, which occurs when the follower M moves to the rear end of the upper slot 88 and is confined to the rear position as it travels downwardly in the cross-over slot 99. Rocking of the lever 80 as aforesaid is against the action of a torsion spring 96 which acts between the arm 54 and the front part 84 of the guide 82.

After the clutch St is engaged or connected between the two shafts 24 and 26, which, as stated above, occurs while the clutch 28 is disengaged, the clutch 28 may be reengaged by returning the member 58 forwardly. However, at this time, the follower 94 travels forwardly in the lower slot 92, which is arcuate about the new position 8 of the pivot 72 of the arm 54, as shown in Fig. 4. With both clutches engaged, power is transmitted to the power take-off shaft 26 and the transmission of power may be intermittently interrupted by disengaging the clutch 28 without disturbing the clutch 30, which will result as long as the member 58 is rocked fore-and-aft with the follower 24 remaining in the lower arcuate slot 92. When it is desired to disconnect the clutch 36), as for prolonged idleness of the power take-oifshaft 26, the member 58 is moved rearwardly, with the follower 94 running in the lower arcuate slot 92, which effects disengagement of the clutch 28. When the follower 94 reaches the intersection of the slots 90 and 92, downward pressure on the handle 80, assisted by the spring 96, causes the follower 94 to travel upwardly in the cross over slot 90, resulting in counterclockwise rocking of the arm 54, which thereby turns the shaft 20 in the same direction so as to shift the clutch 30 rearwardly to its disconnected position. Thereafter, the arm 58 may be returned forwardly by the handle 80, the follower 94- traveling again in the upper arcuate slot 88 so as to reengage the clutch 28 while leaving the clutch 30 disengaged.

Thus, there has been provided an improved power train with two clutches operative in series, plus a simplified control means for operating the clutches in the aforesaid sequence by means of the single control handle and the related linkage and guide means. Features other than those described above will readily occur to those versed in the art, as will many modifications and alterations in the preferred embodiment disclosed, all of which may he achieved without departure from the spirit and scope of the invention.

What is claimed is:

1. Control mechanism, comprising: a support; an arm rockable on the support between first and second positions and having a pivot thereon spaced from the rocking axis; a member movable on the support independently of the arm and in a plane generally parallel to the plane of rocking of said arm and having a pivot thereon parallel to and spaced from both the rocking axis and the arm pivot; 21 first link connected to the arm pivot and extending generally in the direction of the member to a terminal end spaced from the member pivot; a second link connected to the member pivot and extending to and pivotally connected to the terminal end of the first link on an axis parallel to said pivots; a track follower on one of the links in spaced relation to both pivots; a first guide on the support arcuate about the arm pivot in the first position of said arm and receiving the follower to cause the first link to swing about the arm pivot as the member moves, whereby to avoid rocking of the arm; a second guide on the support generally normal to and leading from the first guide and receiving the follower upon swinging of the first link as the member moves whereby the follower departs from the first guide to enable shifting of the first link and rocking of the arm to its second position; and a third guide on the support leading from the second guide in spaced relation to the first guide and arcuate about the arm pivot in the second position of the arm to cause the first link to swing about said second positioned arm pivot as the member moves subsequently, whereby to again avoid rocking of the arm.

2. The invention defined in claim 1, including: a first shaft rockable on the support and carrying the arm; and a second shaft rockable on the support coaxial with the first shaft and carrying member.

3. The invention defined in claim 2, in which: one of said shafts is tubular and the other shaft is concentrically received within said tubular shaft.

4. The invention defined in claim 1, including: a rigid element on the support having first, second and third slots respectively providing said first, second and third guides.

5. The invention defined in claim 1, including: an extension on the second link beyond the member pivot and affording a handle by means of which the second link is rockable about said member pivot as a fulcrum to cause the follower to follow the second guide.

6. Power transmitting means, comprising: first, second, and third shafts; a first clutch operative selectively to connect and disconnect the first and second shafts; a second clutch operative selectively to connect and disconnect the second and third shafts; a support; an arm rockable on the support between first and second positions for respectively engaging and disengaging the second clutch and having a pivot thereon spaced from the rocking axis; a member movable on the support independently of the arm and in a plane generally parallel to the plane of rocking of said arm for engaging and disengaging the first clutch and having a pivot thereon parallel to and spaced from both the rocking axis and the arm pivot; a first link connected to the arm pivot and extending generally in the direction of the member to a terminal end spaced from the member pivot; a second link connected to the member pivot and extending to and pivotally connected to the terminal end of the first link on an axis parallel to said pivots; a track follower on one of the links in spaced relation to both pivots; a first guide on the support arcuate about the arm pivot in the first position of said arm and receiving the follower to cause the first link to swing about the arm pivot as the member moves to disengage the first clutch, whereby to avoid rocking of the arm and thus leaving the second clutch engaged; a second guide on the support generally normal to and leading from the first guide and receiving the follower 20 upon swinging of the first link as the member moves whereby the follower departs from the first guide to enable shifting of the first link and rocking of the arm to its second position so as to disengage the second clutch 7 While the first clutch is disengaged; and a third guide on the support leading from the second guide in spaced relation to and extending generally in the same direction as the first guide and arcuate about the arm pivot in the second position of the arm to cause the first link to swing about said second positioned arm pivot as the member moves subsequently to reengage the first clutch, whereby to again avoid rocking of the arm and thus leaving the second clutch disengaged.

7. The invention defined in claim 6, in which: the first clutch is a friction clutch and the second clutch is a positive clutch.

References Cited in the file of this patent UNITED STATES PATENTS 

